The present invention relates to reclosable fastener assemblies, such as the kind that is useful for sealing thermoplastic bags. More specifically, the present invention relates to such a fastener assembly which employs a slider by which the fastener assembly is opened and closed, and which provides a visual indicator of when the slider is in its closed position.
Reclosable fastener assemblies are well known in the art, most commonly for use in sealing thermoplastic bags. Such fastener assemblies often include a pair of opposing, engageable closure elements that can be pressed together to form a seal and subsequently pried apart to release the seal. In many such fastener assemblies, commonly referred to as xe2x80x9czippers,xe2x80x9d the closure elements are complementary profiles that interlock when pressed together.
Some typical fastener assemblies are illustrated in U.S. Pat. No. 5,140,720 (interlocking rib and groove elements), U.S. Pat. No. 5,007,143 (rolling action zipper profile), and U.S. Pat. No. 3,173,184 (profiles having alternating hook-shaped closure elements).
Some fastener assemblies include a slider to facilitate engaging and disengaging of the closure elements. The slider rides on the closure elements, and, depending on the direction the slider is moved along the closure elements, the fastener assembly is either opened or closed. A typical slider brackets the closure elements and is configured so as to clamp the closure elements together when moved in one direction and to pry the closure elements apart when moved in the other direction. In some embodiments, the slider will include a separating element that fits between the closure elements in order to pry them apart. Such separating elements are illustrated in U.S. Pat. Nos. 4,262,395 (arrowhead-shaped separating element); 5,007,143 (tapered separating element); 3,173,184 (v-shaped separating element) and 5,067,208 (key-hole shaped separating element).
Certain reclosable fastener assemblies provide tactile and/or audible feedback as the slider moves across the closure elements. These typically involve detents or deformations in the closure elements that affect the feel and/or sound the closure elements produce as they are interlocked, such as in U.S. Pat. Nos. 5,138,750 and 5,722,128, or closure elements that elastically deform when interlocked, such as in U.S. Pat. No. 5,774,955. The former type provides feedback while the slider is being moved, but no real indication as to whether the fastener assembly is closed or open once the slider is at an end of the closure elements. The latter type does provide an indication of when the fastener assembly is closed, but that indication is rather subtle.
Other reclosable fastener assemblies provide visual feedback when the closure elements are engaged. These typically involve providing colored closure elements that combine to produce a color change when the closure elements are interlocked. Some examples are illustrated in U.S. Pat. Nos. 4,829,641; 4,907,321 and 5,356,222. Unless the closure profiles are sufficiently separated, this arrangement is only helpful when the user remembers which color indicates an open position of the closure elements.
Thus, it is not always easy for a user to tell at a glance whether a fastener assembly is closed or open. This is especially true for fastener assemblies that employ sliders, because the action of the slider typically does not separate the closure elements far enough that it is visually obvious when the fastener is open. Therefore, there is a need in the art for a reclosable fastener assembly, employing a slider, whereby a visual indicator is provided as to whether the slider is in its fully closed position.
The reclosable fastener assembly of the present invention addresses the foregoing needs in the art by providing complementary partial indicators that combine to form a visual indicator when the slider is in the closed position.
According to one aspect, the present invention relates to a reclosable fastener assembly, including first and second elongated closure elements engageable to form a seal. A slider is slidable relative to the closure elements between an open position and a closed position and is adapted (i) to engage the closure elements to one another when moved across the closure elements toward the closed position and (ii) to disengage the closure elements from one another when moved across the closure elements toward the open position. The slider carries a first partial indicator. A second partial indicator is located relative to the closure elements so as to complement the first partial indicator to form a visual indicator when the slider is in the closed position.
Preferably, the second partial indicator is stationary relative to the closure elements. Generally, the second partial indicator is located near an end of the closure elements.
The first and second partial indicators can comprise complementary portions of a pattern. The pattern can be a word, in which case the first and second partial indicators can include complementary portions of individual letters of the word. The pattern can also depict an object, which can be three dimensional.
A stop can be disposed so that the slider abuts the stop when the slider is in the closed position, and the second partial indicator can be provided on the stop.
Alternatively, the slider can include an opening through a side of the slider, and the second partial indicator can comprise a visible feature that is located so as to be visible through the opening of the slider when the slider is in the closed position. A pair of the openings can be provided, one each through opposite sides of the slider, in which case a pair of the visible features can be provided, each located so as to be visible through a different one of the pair of the openings of the slider when the slider is in the closed position. The feature can be provided on the surface of one of the closure elements, and can be a pigmented spot, for example.
According to another aspect, the present invention relates to a reclosable fastener assembly for selectively closing a mouth of a thermoplastic bag. The fastener assembly includes first and second elongated closure profiles disposed on opposing surfaces of the mouth of the bag. The first and second closure profiles are interlockable to seal the mouth of the bag. A slider brackets the closure profiles, and is slidable relative to the closure profiles between an open position and a closed position. The slider is adapted (i) to interlock the closure profiles when moved across the closure profiles toward the closed position and (ii) to disengage the closure profiles from one another when moved across the closure profiles toward the open position. The slider carries a first partial indicator. A second partial indicator is disposed relative to the closure profiles so as to combine with the first partial indicator to form a visual indicator when the slider is in the closed position.
These and other objects, features and advantages of the present invention will be more apparent from the following description of the preferred embodiments, with reference to the following drawings, in which like reference numerals refer to like elements throughout.